1. Field of the Invention
The present invention relates to a cleaning apparatus, and more particularly, to a reticle cleaning apparatus for a wafer exposure system. Although the present invention is suitable for a wide scope of applications, it is particularly suitable for cleaning a reticle just before a wafer exposing process.
2. Discussion of the Related Art
Conventionally, a reticle is manually taken out one by one from a reticle carrier storing a plurality of reticles before a patterned reticle is transferred into a reticle cassette library in an exposure system. A nitrogen gun connected to a nitrogen supply device is then aimed at the surface of the reticle and triggered accordingly in order for the nitrogen gas released from the nitrogen gun to carry out a cleaning operation of the reticle.
FIG. 1 is a flow chart illustrating a path of reticle received in an exposure system according to the background art. A plurality of reticles received in a reticle cassette library 1 are moved by a reticle robot 2 one by one into an interim storage unit 3 so as to separate a cover enclosing the reticles. The reticles separated by the interim storage unit 3 are moved by the reticle robot 2 to a turn table 4 and then to a reticle stage 5.
However, in the conventional exposure system using a manual cleaning method, the reticle has to be cleaned through a plurality of steps before and after receiving into the exposure system. Consequently, undesired exterior substances, such as dust, may be attached on the surface of the reticle, thereby interfering a scanning light during the exposure process. As a result, a reticle pattern is not appropriately printed onto a photoresist film on a target wafer.